I have f(x,y,z)=(x^2)y-x(e^z) and point Po=(2,-1,pi)(adsbygoogle = window.adsbygoogle || []).push({});

I need to find

a) gradient at point Po ( done)

b) Rate of change of f at point Po in the direction of vector u=i-2j+k (it's also done)

c) Unit vector in the direction of fastest growth of f at Po.

I can't find formulas for a last on. Does it come from a) and b)?

I know that angle should be zero but I am not sure what angle it is.

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# Homework Help: Dirction of fastest growth

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